Thomas leavbra



N nmrnnsrnrns 'nHoMAs Lnevrrr,.orlvlALiDnN,iivnaggigy@Ems` i Saawmenoemcaea specification of Letters Patent No. 26,684, .dated Jnuryl; i850 To allwho'm it may conce/m. i 1

Be it known that I, THOMAS LEAvrTr, of

Malden, `in the county of Middlesex and State of Massachusetts, have invented an Improvement on the Second Anchor`q` Shackle and on an Improvement in Mesi i senger Shackle-Blocks, both patented to George Gilmour on the th day of March and on the 21st; day ofApril, A. D. 1857,

`10 respectively g. :and I do hereby declare that` those skilled in the art to make and usemy invention. i, n

Of the drawings, Figure l is aside view of a Messenger shackle block constructed with my improvement, and arranged ready to be slipped upon a chain. Fig. Qfis a plan of the same. Fig. 3 is a sectional View` of the roller (a) exhibiting one form` of my improvement, and Fig. 7 is a view ofa simif lar roller as commonly constructed and without my improvement. Figx is aside view of that part of either an anchor shackle, or shackle block, with which my improvement is immediately connected. Fig. 5 is a plan of the same with the roller (b) in the position it occupies when upon the chain.` Fig.

6 illustrates the position and connection of roller (t) with the other parts, when arranged to be slipped upon the chain.

Previous to my improvement, the roller which facilitates the movement of the shackle block on the chain, had been so constructed that, in order to place the shackle upon the chain, it became necessary to remove the bolt (c) Fig, 7 entirely from the shackle,\which left the roller loose, and it,

as well as the bolt, became the object of special care to the operator; for if either of t e parts, bolt or roller, were lost, the shackle was, for the time, rendered useless.

p e5 The care and exertion required for the re-` tention of the bolt and roller, when the operative is swung over the bows of a vessel, endeavoring to slip the shackle on the chain cable, when she is pitching her bows in and out of the water, and rollingheavily,

and where the roller weighs, as it often does, more than fifty pounds, is obvious; it isalways under any circumstances a drawback to the use of Gilmours otherwise efcient apparatus, and under unfavorable circumstances renders its use impossible.

l The @wearer.imyliava1-I the apparatus `vvhen if? the?? shack the i described "defect inl y before referredtdfand "tshn l the means described,`o` lt. l' t equivalents, i of lso constructing 1 the rolle to have it` connected lwiththeyfoth'er pail; i y

slipped upon {orftaken from theycha n,` not separable from dt, accidentally,un any i circumstances, `{while 3 lat the` sain provision `may be made z` for separating roller from` the other y partsffforl repairs As this inveiitioniis anllimll'tvemeri a well known matterlI scription nearly "as ment.

that the roller (dyissupp rtedl eenthe cheeks (e) on aplain bolt(c)whichfpasses e through the `cheeks gis,securedbyiaspin in the pin hole` shovvnfinthetbelt."` lThis fi the methodof attaching and securingth` roll in Gilmourlslsecond anchornshacklegand` 1 Messenger shackle blolckl` Itis evidenttify) the pin be withdrawn from.. the pin` hole,` U that, in some positionsathe bolt caniaiidvvill` t work clear from` allthe parts, and .tliatfthenf le lf3 3 the rolleris entirely free. lt is true thatlfthe bolt may be connedtoone ofthe cheeks by` a chain, as is common for securingwsimilart: bolts and pins, and so thatif the boltshould e get adrift it would not `bei losta` Butnolsuchf .l y

securitycan be hadvforjthe roller; Iffit` l gets adrift `accidentally itfis .lost,;andlfthel"9c same result `"attends neglgng, @dentmr inability on the part` of tie Operative;

AS GlmOurS `apparatus\(thegewild u1 l chor shackle especially)`isla "safetyldw e. i

therefore atlife and `property l preservir1g-,"95f;` apparatus. The utility and gimportancefof-` 1" any change therein which detractsfrom `it liability to` accident, and consequent ineili ciency, is too obvious `to need further"comi-` 3p y ment. i i H e l Q`V"lj100"` In Figs. l and l2, where oneofthe cheeks` l l (e) can be movedyindependently ofitheg 1" other, the roller `maybe constructedwithfa cha mbered axial .bore, shown :in dottedflinesf Fig. 2, and in detailfin FigLB. The bolt( f)l 110` l is constructed withaj head, `or shoulder@ larger than the bodyoftheholt, softhat y when the fastening,` ofwhatever kind,fe1n` ployed to hold thebolt inthe cheeks,"isre p moved the `bolt can be withdrawngsothat the end by which it issecuredlwillybeenf1 tirely within thelroller,` whichjgwillf allovv,` f1,

Y dotted lines.

one cheek to be swung past the roll, as shown in Fig. l, for the purpose of slipping the shackle on or olf the chain cable. of fastening employed to hold the bolt or roller between the cheeks, and shown in Figs. l, 2 4 and 5 consists of-a latch (i) which is thrown into a recess formed in the bolt or roller, as plainly shown in the drawings, by a spring acting on a pin in the latter, both pin and spring being shown by Any other` method of confining the bolt or roller, such as a pin, or key, or split spring pin, or nut, will serve a good purpose, and the manner of their application for the Ypurpose is obvious.

In order to insert the bolt in the roller, when both are constructed similarly to those shown in Figs. 2 and 3, the head g) should be made separate from the bolt and riveted on.

Figs. 4, 5, and 6, illustrate a manner of constructing the roller which I prefer to any other; for by it the boring of the roller and the construction of the bolt is saved, and besides the cheeks (e) can be fastened together, and the shackle can be placed upon and takenv off the chain by simply removing the fastening at one end of the roller and The kind' withdrawing it from and out of one cheek, when it will'be supported and heldsecurely by the other. This roller is inserted into suitable holes formed in the cheeks before they are riveted or otherwise fastened to-- gether. The end of this roller where it is secured by the latch may be otherwise fashioned 'for any suitable fastening.

It is evident that the detail of arrange- THOMAS LEAVITT.

Witnesses:

J. B. CROSBY, W. B. GLEAsoN. 

